Metallics JFSCM1230Z Screw M12 x 30 Din 7991-10.9 SHCS FH (Jar 100)

It's an M12 x 30 mm flat head socket cap screw to DIN 7991, property class 10.9, with a zinc finish. Flat head socket cap means a countersunk head driven by a hex key, so it sits flush in an 82-90 degree countersunk hole rather than standing proud like a standard socket cap. Sold as a jar of 100.

The M12 x 30 screw needs a 90 degree countersunk hole so the head finishes flush with the surface, over a clearance hole for M12 (13 mm is the standard clearance). If your material isn't thick enough to take the countersink, use a standard socket cap or hex head screw instead; forcing a flat head into a shallow countersink leaves the head proud and the joint under-seated.

DIN 7991 M12 screws are supplied in coarse thread, M12 x 1.75. They will not thread into an M12 x 1.5 fine pitch hole. If your tapped holes or nuts are fine pitch, this is the wrong screw for that joint.

Property class 10.9 is a high strength alloy steel grade, so the M12 x 30 screw is the grade typically specified for structural brackets, machine frames, and strut or equipment mounting. Keep in mind that any countersunk flat head screw has a smaller head bearing area than a hex or socket cap head, so it relies on the countersink for load transfer, not on a washer face. Don't use it with a flat washer under the head.

The JFSCM1230Z is zinc plated, which is an indoor and sheltered-use finish. It handles normal interior humidity and construction handling, but for direct weather exposure, wash-down, or coastal work you want stainless or hot dip galvanized hardware instead. Note that high strength 10.9 fasteners are generally electroplated rather than hot dipped, so a zinc plated 10.9 is the normal offering in this grade.

Each jar holds 100 of the M12 x 30 screws. The jar format is what maintenance and electrical crews keep on the shelf or in a van bin, so it suits standardizing one fastener size across a facility rather than buying per job.